mybatis的if标签判断子类属性-There is no getter for property named 'export' in

1

 <select id="findList" resultType="BndExport">
         SELECT
             <include refid="bndExportColumns"/>
         FROM bnd_export a
         <include refid="bndExportJoins"/>
         <where>
             a.del_flag = #{DEL_FLAG_NORMAL}
             <if test="createDate != null and createDate != ''">
                 AND a.create_date = #{createDate}
             </if>
             <if test="createDateStart!=null and createDateStart!='' and createDateEnd!=null and createDateEnd!=''">
                 AND a.create_date between to_date('${createDateStart}','yyyy-mm-dd hh24:mi:ss') and to_date('${createDateEnd}','yyyy-mm-dd hh24:mi:ss')
             </if>
             <if test="company != null and company != ''">
                 AND a.company = #{company}
             </if>
17             <if test="bndExportFreight != null and bndExportFreight != '' and bndExportFreight.vessel != null and bndExportFreight.vessel != ''">
                 AND b.vessel= #{bndExportFreight.vessel}
             </if>
             <if test="bndExportFreight != null and bndExportFreight != '' and bndExportFreight.voyage != null and bndExportFreight.voyage != ''">
                 AND b.vessel= #{bndExportFreight.voyage}
             </if>
         </where>